Button for a watch



FIG. 1 is a front, right side, top perspective view of a button for a watch showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken line showings are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a button for a watch, as shown and described. 